As disclosed in the patent literature, perfluoroalkylene ether bibenzoxazole polymers possessing a high degree of thermooxidative and hydrolytic stability as well as low glass transition temperatures can be readily synthesized. Examples of such polymers are disclosed by one of us in U.S. Pat. Nos. 3,846,376; 3,994,861; and 4,005,142. Because of the properties of the polymers, they have shown promise as candidate materials for advanced aerospace applications involving severe environments. A problem encountered with the prior art polymers involves the difficulty in curing them to a satisfactory elastomer. While the polymers can be cured to elastomers, the process is difficult and requires relatively extreme conditions. In addition, the mechanical properties of the resultant elastomers require upgrading in order to meet the rigid requirements of aerospace applications.
It is an object of this invention, therefore, to provide perfluoroalkylene ether bibenzoxazole polymers containing hydrocarbon cure sites so that the polymers can be readily cured to elastomers exhibiting good mechanical properties in severe environments.
Another object of the invention is to provide perfluoroalkylene ether bibenzoxazole polymers possessing a high degree of thermooxidative and hydrolytic stability as well as low glass transition temperatures.
A further object of the invention is to provide a method for synthesizing the bibenzoxazole polymers.
Other objects and advantages of the invention will become apparent to those skilled in the art upon consideration of the accompanying disclosure.